JP2008536125A5 - - Google Patents

Claims (10)

A method of distinguishing a control solution from a sample during operation of an electrochemical sensor that measures the amount of analyte in the control solution and sample:
(A) adding to the control solution an internal reference compound configured to be electrochemically oxidized at a potential higher than that required to measure the oxidation of the analyte;
(B) introducing a control solution containing an internal reference compound and a predetermined amount of an analyte into an electrochemical sensor having a working electrode and a counter electrode, and a reagent;
(C) applying to the electrochemical sensor at least one potential sufficient to oxidize the internal reference compound and the analyte and measuring the resulting current;
(D) At least one potential that is lower than the potential of (c) in the electrochemical sensor and sufficient to measure the oxidation of the analyte of interest, but insufficient to oxidize the internal reference compound. Applying multiple times and measuring the resulting current;
(E) DI = i _{high volt} / i _{low volt where} i _{high volt} is the current value measured in (c) and i _{low volt} is the current value measured in (d) Calculating a differentiated differential index (DI);
(F) determining that a control solution is present if the differential index in (e) is sufficiently greater than 1 to distinguish the internal reference compound from a predetermined amount of analyte; and (g) (e) Determining that a sample is present if the differential index at is about 1;
Including said method.   The method of claim 1, wherein the differential index determined in (f) is 1.5 or higher.   The method of claim 1, wherein the internal reference compound is added in an amount proportional to the amount of analyte present in the control solution.   A first potential sufficient to oxidize the analyte is applied for a first predetermined time, followed by a second potential that is less than the first potential insufficient to oxidize the analyte. 2. The analyte of interest is measured by applying a predetermined time and then applying a third potential higher than a second potential sufficient to oxidize the analyte for a third predetermined time. Method.   The method of claim 1, wherein the analyte is glucose and the sample is whole blood.   The method of claim 1, wherein the internal reference compound is an oxidizable organometallic compound, a coordination compound, or an organic amine compound. Internal reference compounds are 3- (N-morpholino) propanesulfonic acid, N- (2-hydroxyethyl) piperazine-N ^1- (2-ethanesulfonic acid), 2- [2-hydroxy-1,1-bis ( Hydroxymethyl) ethylamino] ethanesulfonic acid, 2-morpholinoethanesulfonic acid, and Bis (2-hydroxyethyl) amino-tris (hydroxymethyl) methane [Bis-Tris], 4-aminobenzonitrile, 4-aminobenzoic acid Or an organic amine compound that is 4-iodoaniline.   7. The method of claim 6, wherein the internal reference compound is a coordination compound that is potassium ferrocyanide. (A) a predetermined amount of the analyte of interest; and (b) configured to be oxidized at a potential higher than that required to oxidize the analyte of interest so that the presence of an internal reference compound can be detected. The predetermined amount of the internal reference compound is proportional to the predetermined amount of the analyte, the predetermined amount of the internal reference compound;
A control solution used in testing an electrochemical system for measuring the amount of an analyte in a sample. A method for distinguishing a control solution from a sample during operation of an electrochemical sensor for measuring the amount of an analyte of interest:
Prepare a control solution that is an internal reference compound that has a potential higher than that required to measure the oxidation of the analyte and is different from the buffer, including a buffer and a predetermined amount of the analyte. Process;
Providing an electrochemical sensor having a working electrode and a counter electrode;
Introducing the control solution into the electrochemical sensor;
Applying a sufficient potential to the electrochemical sensor to oxidize the internal reference compound and the analyte and measuring the resulting current;
Applying a lower potential to the electrochemical sensor sufficient to oxidize the analyte of interest but not sufficient to oxidize the internal reference compound and measuring the resulting current; and measured current Determining whether a control solution or sample is present based on:
Including said method.